Malignant melanoma and overlapping cancers over the past decade in our department

Abstract

Malignant melanoma is a cutaneous tumor characterized by the malignant transformation of melanocytes. It is associated with a high rate of lymph node and distant metastasis, as well as a high recurrence rate. In Japan, there has been a gradual increase in the incidence of multiple cancers. From 2013 to 2023, we investigated the incidence of multiple cancers in 114 patients treated for malignant melanoma at our department. Among these patients, 23 (mean age, 73.1+8.4 years) had multiple cancers, with 4 having prior malignant melanoma, while 19 developed subsequent malignant melanoma.

No clear pattern was observed in the types of overlapping cancers. In patients with prior malignant melanoma, the average time to the development of overlapping cancers was 1.7 years. These findings indicate a rising incidence of overlapping cancers in patients with malignant melanoma, highlighting the need for vigilance for such occurrences in future clinical practice.[Skin Cancer (Japan) 2024 ; 39 : 49－54]